1. Field of the Invention
This invention pertains to the field of waste disposal and, more particularly, to the field of closed cycle waterless flush toilet systems.
2. Prior Art
There are many sanitation requirements which cannot be met by conventional sanitation solutions. For example, many locations where sanitation facilities are needed do not have public sewers and cannot accommodate septic tanks because they are prohibited or impractical. Also, many such locations do not have an adequate supply of water to accommodate conventional water flush toilets.
There are existing waterless flush toilet systems that overcome many of the previously noted problems. A system manufactured by the Sarmax Corporation of Laguna Niguel, California is typical of such systems. The Sarmax system comprises one or more flush toilets connected to a main holding tank, the tank being disposed at an elevation lower than that of the toilets. A supply of a nonaqueous flushing fluid comprised of a highly refined mineral oil and various additives is stored within the holding tank. The flushing fluid is lighter than and insoluble in the waste material which is also held in the tank. The fluid, therefore, tends to collect on the surface of the waste material so as to form a stratified layer thereon. A smaller quantity of the flushing fluid is also stored in individual "water closet"-type tanks positioned above each toilet.
When a toilet is flushed, a valve in the "water closet" is opened, permitting the fluid stored therein to enter the toilet and flush away the waste material. The fluid and waste material are fed by gravity to the main holding tank where the fluid separates from the waste material and becomes part of the stratified layer. When a toilet is being flushed, flushing fluid is simultaneously drawn up from the stratified layer in the tank to replace the fluid lost from the "water closet".
A fluid pickup device is disposed within the tank which floats within the surface layer of fluid regardless of the waste level within the tank. The float includes a plurality of fluid inlets which are connected to at least one flexible hose which exits through the top of the tank. A pump is used to draw the flushing fluid up through the pickup device fluid inlets, through the hose and then to the individual "water closets."
Once the tank becomes filled, a line from a vacuum pump truck is connected to the waste outlet located at the top of the tank. A pump down tube which is connected to the waste outlet extends from the top of the tank to the tank bottom, so that waste material is drawn up from the bottom through the tube into the pump truck. Not all of the waste material is removed during pump down. When the level of the waste and the flushing fluid strata drops to a predetermined point, automatic means prevents further pumping so that none of the flushing fluid is removed.
The presently existing waterless flush toilet systems solve many sanitation problems in locations where water flush toilets are not practical. However, such prior art systems possess many shortcomings. The Sarmax system, for example, is quite complex, utilizing electronic controls and the like. Furthermore, such systems are very bulky and not suitable for many applications, such as vehicles. A system is needed which is simple and does not incorporate complicated control means. Such a system would be more reliable than prior art systems and much less expensive. Furthermore, a system is needed which is compact and can be used in locations where space is at a premium, such as in mobile homes, buses, aircraft, boats or the like.